{
  "abstract": "Stars embedded in the disks of active galactic nuclei (AGN) can grow to hundreds of solar masses, and the same disks are expected to host a population of stellar-mass black holes. A star may therefore capture passing black holes, turning its interior into a potential factory for forming compact binary black hole systems and, ultimately, for the gravitational-wave events seen by our detectors. We test how readily this channel operates using three-dimensional hydrodynamic simulations of black hole--star encounters. As a proof of principle, we adopt a star-to-black-hole mass ratio of $34\\!:\\!1$, and find that the capture does not disrupt the structure of the star: it heats the star by $10$--$30\\%$, and the star loses only $\\lesssim1\\%$ of its mass throughout. The captured black hole loses its orbital angular momentum rapidly to dynamical friction, sinking to the stellar center within a stellar dynamical time $\\lesssim10^{4}\\,$s. If the star already harbors a black hole at its center, the two form a bound binary whose gravitational-wave coalescence time falls below $10^{4}\\,$yr. Depending on the geometry and speed of the encounter, the resulting orbit may be nearly circular or retain substantial eccentricity. Our calculations confirm that black hole--star encounters in AGN disks are indeed a viable channel for assembling stellar-mass black hole binaries and supplying sources for gravitational-wave detectors.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.16290",
  "author_total": 3,
  "authors": [
    {
      "name": "Sizheng Ma"
    },
    {
      "name": "Douglas N. C. Lin"
    },
    {
      "name": "David A. Velasco-Romero"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5xdh85sbb0ssy.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.16290",
  "fulltext_url": null,
  "id": "5xdh85sbb0ssy",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.16290",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "arxiv",
      "astro-ph.HE"
    ],
    [
      "arxiv",
      "astro-ph.SR"
    ],
    [
      "arxiv",
      "gr-qc"
    ],
    [
      "openalex",
      "3103|Pulsars and Gravitational Waves Research"
    ]
  ],
  "openalex": "W7213393202",
  "pdf_url": "https://arxiv.org/pdf/2609.16290",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-14",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5xdh85sbb0ssy.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:41Z",
      "native_id": "2609.16290",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.16290"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    },
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    }
  ],
  "title": "Formation of Merging Black Hole Binaries Inside Massive AGN Stars",
  "title_text": "Formation of Merging Black Hole Binaries Inside Massive AGN Stars",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:41Z",
  "url": "https://research.draconitic.com/paper/5xdh85sbb0ssy",
  "venue": "arXiv",
  "versions": []
}